Objective: The human genome contains numerous active transposable elements (TEs), including the inserts of young Alus such as AluYa5 and AluYb8. The rapid, human lineage-specific evolution of brain size may be influenced by natural selection and the genomic variation of TEs, which can act as catalysts of evolution. Given their potential effects on human brain development, Alu elements may also be relevant in exploring complementary approaches for psychiatric disorders. This study analyzed the potential impacts of three specific Alu insertions (AluYa5-ACE, AluYa5-PROGINS, and AluYb8-MUTYH) on the susceptibility to panic disorder (PD). Materials and Methods: Alu insertions were determined with Polymerase Chain Reaction (PCR) method in 120 PD patients and 120 healthy control individuals and analyzed with logistic regression. The associations of the investigated Alus with both categorical and quantitative demographic-clinical variables including the Panic Disorder Severity Scale (PDSS) were analyzed using Fisher's exact and Kruskal-Wallis tests. Results: AluYa5-PROGINS and AluYb8-MUTYH did not show an association with panic disorder risk. For AluYa5-ACE, a statistically significant association was determined; logistic regression analysis proved the highly protective effect (47.9%) of I/D genotype against PD compared with D/D genotype (p=0.030, OR=0.521, 95% CI=0.290-0.937). Alu insertions were not associated with panic disorder severity (p>0.05). Conclusion: This is the first combined study in which the potential effects of three Alu insertions in terms of both PD susceptibility and possible association with several disease parameters were evaluated. Further studies about the roles of the Alu elements in the etiology PD are highly recommended.
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